It is a common and debilitating consequence of neuromyelitis optica spectrum disorder (NMOSD) myelitis, with no satisfactory treatment.
The IASP's widely used definition of pain states: “Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.”
Does not involve sympathetic hyperactivity but may be associated with vegetative signs (eg, fatigue, loss of libido, loss of appetite) and depressed mood. People vary considerably in their tolerance for pain.
Up to 7% to 8% of the European population is affected, and in 5% of persons it may be severe.
Neuropathic pain may result from disorders of the peripheral nervous system or the central nervous system (brain and spinal cord). Thus, neuropathic pain may be divided into peripheral neuropathic pain, central neuropathic pain, or mixed (peripheral and central) neuropathic pain.
Peripheral neuropathic syndromes have received greater attention in the research literature than central pain, and studies of syndromes such as postherpetic neuralgia and painful diabetic neuropathy provide the basis for current knowledge of neuropathic pain.
Peripheral nerve injury is associated with microvascular disturbance; however, the role of the vascular system has not been well characterized in the context of neuropathic pain.
Is caused by damage or disease that affects the somatosensory system.
Patients with neuropathic pain are usually more heavily burdened than patients with nociceptive pain. They suffer more often from insomnia, anxiety, and depression. Moreover, analgesic medication often has an insufficient effect on neuropathic pain.
It may be associated with abnormal sensations called dysesthesia, and pain from normally non-painful stimuli (allodynia). Neuropathic pain may have continuous and/or episodic (paroxysmal) components. The latter resemble an electric shocks. Common qualities include burning or coldness, “pins and needles” sensations, numbness and itching. Nociceptive pain, by contrast, is more commonly described as aching.
The presence of neuropathic pain can severely impinge on emotional regulation and activities of daily living including social activities, resulting in diminished life satisfaction. Unfortunately, the majority of patients with neuropathic pain do not experience an amelioration of symptoms from conventional therapies, even when multimodal therapies are used. Chronic refractory neuropathic pain is usually accompanied by severe depression that is prone to incur suicidal events; thus clinical management of chronic neuropathic pain and depression presents a serious challenge for clinicians and patients 1).
Two patients presented with neuropathic pain and severe depression. The patients had different pain symptoms emerging a few months after central or peripheral nervous system impairment. These symptoms were associated with the development of severe depression, social isolation, and a gradual inability to perform daily activities. Both patients were referred for bilateral anterior cingulotomy. After surgery, both patients showed significant progressive improvements in perceived pain, mental health status, and daily functioning.
Bilateral anterior cingulotomy may serve as an alternative treatment for medically refractory neuropathic pain, especially for patients who also experience depression 2).